Paraffin scraper



April 2, 1963 R. R. NAGEL ETAL 3,083,773

PARAFFIN scRAPER Filed Aug. 4, 1961 /VaJ/z 0. Cam/7 /Je INVENTORJ Afro/wf ya 3 slippage is increased, the force pressing the stop lug against the sucker rod is increased and directed so as to prevent such slippage of the scraper d2 on the sucker r-od. It is noted that the s-top lug 26 may be simply and easily manufactured by utilizing the punched out portion from the locking slots 24.

Of course, various-modifications of this paraiiin scraper may be made utilizing the basic spring metal body which snaps on and locks on Ia sucker rod. FIGURES 3 and 4 illustrate a modification of the paraffin scraper according to the invention, the letter a being applied to parts corresponding to those in FIGURES l and 2 for convenience of reference. In the modiiication shown in FIGURES 3 and 4, the locking lugs and slots have been omitted, and the pressure sensitive adhesive has been omitted, but a plurality of indentations 28 may be provided, if desired, around the interior of the curved portion 12a of the scraper a. Thus, as the resilient spring metal curved portion 12a is compressed :around a sucker rod the indentations 28 will provide additional pressure and holding means Ito secure the scraper 12a to 'the sucker rod.

In addition, a plurality of `stop lugs 30', here shown as one for convenience, may be provided which are connected closer to the free end of the blade Zita than the embodiment shown in FIGURES l and 2. This insures that a greater leverage will be exerted on the stop lug 3d against the outer periphery of the sucker rod 14 as the scraper 12a is rotated in a clockwise direction. This provides `a structure which will increase the force to prevent slippage between `the scraper E21: and the sucker rod 14. It is also noted that the lug 3d readily allows the scraper 16a to be slipped over the sucker rod 14, but blocks the opening 16a to prevent lateral movement oli of the vrod 14 by the scraper 12a.

It is particularly noted that the paraiiin Scrapers 19 and 10a can be used for counter clockwise rotation as Well as clockwise rotation without requiring any structural modifications. That is, the Scrapers 1d` and 10a merely need to be inverted on the sucker rod 14 for counter clockwise rotation and thus have the forces act-V ing on the blades 2@ and 20a 4and on the stop lugs 2d and 30 Ito holdthe scrapers on the rod 14 and to preventV slippage between the scrapers and the rod 14.

Thus', the present invention provides a paraffin scraper which may be quickly and easily snapped in pl-ace upon a sucker rod and requires no welding, bolts, or holes to be drilledl in 'the sucker rod for attachment. Similarly, the paraiiin scraper of the present invention can be quickly and easily detached and removed from a sucker rod. In addition, the present paraiiin scraper is made in` aI unitary body which facilitates the ease of handling and attachment. Furthermore, itis particularly noted that the parain scraper of the present invention can be inexpensively `and quickly manufactured out of `a single plate of springv metal such as steel, by a suitable die, and thus will provide an extremely inexpensive and yet suitable device.

In operation, generally a plurality of paraflin scrapers are attached to the sucker rod 14 of a pumping oil well. As is conventional, a plurality of these paraflin 'Scrapers are placed along the sucker rod at a distance less than the longitudinal stroke of the rod,A Thus as the rod is longitudinally moved and rotated the Scrapers will prevent the well tubing from becoming caked up with paraiiin so as to reduce the flow of well'tluid being pumped.

YThe paran scraper of the present invention can be quickly and easily snapped on and locked onto aksuckevr rod at the desired position. The embodiment shown in FIGURES I and 2 maybe quickly andv easily fastened together by passing resilient locking Il ugs 22 Ithrough the slots 24 and allowing .themv to catch on the outer edge of the'scraper body 12. However, the locking lugs and slotsV may be Vomitted and the scraper 12 may be held in place bythe resilient action of the spring metal body curved portion 12 and 12a used for the device. In adi dition, if desired, other features of the device such as the pressure sensitive adhesive 18, or the indentations 28 (FIGURE 4) or both may be utilized to assist in securing the scraper on a sucker rod.

The use of V-a stop lug is advantageous in preventing slippage of the scraper 12 or 12a around the rod 14. It is noted that the stop lugs 26 and 3% while `allowing the scraper to be passed over and snapped on to the sucker rod, tend to catch and prevent accidental disengagement of the scraper from the sucker rod. It is also noted that :as vthe paraffin scraper is rotated in the well the blade 20 will suitably scrape a tubing 0i paraiin or other matter which prevents the flow of fluid. As the blades 20 and 20a encounter and scrape this matter a force is exerted on these blades which will tend to wrap them further around the sucker rod and .thus tighten the scraper on the rod as well as further forcing the lstop lugs 25 and 30 against the outer periphery of the sucker rod to prevent slippage of the scraper on the sucker rod.

Advantageously, the device of the present invention can be positioned on the sucker rod 14, as shown in vthe drawing or inverted. Thus, depending on the direction of rotation of the sucker rod y14, the paraffin scraper ltl and 19a can berpositioned so that the scraping force acting on the blade extension 2t) and 20a acts in a direction .to both tend to wrap the blade about the rod and acts to force the lstop lug 26 and 30' against the rod to prevent slippage. Thus, if the rod i4 were rotating in a counter clockwise direction, the paratlin scraper 1li' land lila would be connected to the rod in an inverted position from that shown in the drawing so that the blade and the stop lugs would be positioned so as to lead the opening 16 and 16a in .the direction of rotation when. 'the scraper is rotated.

Thus, the parafn scraper lof the present invention is particularly advantageous in providing an integral resilient spring holding body which grips and secures the scraper to a sucker rod by a snap on action. The scraper body may be provided with indentations oradhesive pressure means for further securing the scraper to the sucker rod. The scraper may further utilize a stop lug which acts to prevent slippage of the scraper on the sucker rod in proportion to the force tending to create such slippage. In addition, it is particularly noted that this integral paraffin scraper is particularly easy to manufacture and inexpensive.

The present invention, therefore, is well adapted to carry out the obiects and attain the ends andl advantages mentioned as well as others inherent therein. While presently preferred embodiments of the invention are given for the purpose of disclosure, numerous changes inl the details of construction and arrangement of parts will readily suggest themselves to those skilled in the art and which are encompassed within the spirit of the invention and the scope of the appended claims.

What is claimed is:

l. A paraiiin scraper for use on a sucker rod comprising, a unitary body of resilient spring steel and including a. tubular portion having an axial opening and Sized to snap on and secure the resilient'body to a sucker rod, and a blade portion connected to said tubular portion and extending outwardly to scrape paraiiin from a Well tubing, said blade connected to said tubular portion and extending from one side of the opening and adapted to be positioned on the leading edge of the opening when the rod is rotated thereby tightening the scraper on the rod, locking lugs extending from the body on one side of the opening, and stop lugs being pressed from 4the body on the second side of the opening leaving receiving slotsA for said locking lugs.

2. A paraiiin scraper for use on a sucker rod comprising, a unitary tubular body of resilient spring steel, said body including an axially extending opening and sized to it around and snap on and hold the body to a sucker rod, a `blade portion extending outwardly from the body at one side of the opening to scrape paraffin from a well casing, said blade adapted to be positioned on the leading edge of the opening when the rod is rotated thereby tightening the scraper on the rod, and a stop lug on the body and extending angularly therefrom, said lug adapted to be directed opposite from the direction of rotation of the rod, said stop lug positioned interiorly of said body and in said opening so as to engage the outer surface of the rod at an angle thereby preventing slippage between the scraper and the rod.

3. The invention of claim 2 including a pressure sensitive adhesive material on the interior of the body for holding said scraper to the rod.

4. The invention of claim 2 including protuberances on the interior of the body.

5. The invention of claim 2 including locking lugs connected to the body on one side of the opening, the body having receiving slots for said locking lugs on the other side of said opening.

6. The invention of claim 2 wherein the stop lug is connected to the blade portion of the body.

7. A parafn Scraper for attachment to a sucker rod comprising, a unitary tubular body of resilient spring material, said body having an axially extending opening along the entire length of said body and sized to t around and snap on and hold the body to a sucker rod, a blade portion extending outwardly from the body at one side of the opening to scrape paraffin from a Well casing, said blade adapted to be positioned on the leading edge of the opening on rotative movement between the rod and tubing thereby tightening the scraper on the rod, and a stop lug extending from the body and positioned in said opening and adapted to contact the sucker rod, said stop lug positioned to be at an `angle to and directed toward the rod when the scraper is attached thereto thereby preventing slippage of the scraper on the rod.

References Cited in the tile of this patent UNITED STATES PATENTS 2,014,723 Di Carlo Sept. 17, 1935 2,321,275 Blackburn June 8, 1943 2,658,246 Mahler Nov. 10, 1953 2,947,055 McHenry Aug. 2, 1960 FOREIGN PATENTS 117,247 Sweden Sept. 17, 1946 758,348 Great Britain Oct. 3, 1956 

2. A PARAFFIN SCRAPER FOR USE ON A SUCKER ROD COMPRISING, A UNITARY TUBULAR BODY OF RESILIENT SPRING STEEL, SAID BODY INCLUDING AN AXIALLY EXTENDING OPENING AND SIZED TO FIT AROUND AND SNAP ON AND HOLD THE BODY TO A SUCKER ROD, A BLADE PORTION EXTENDING OUTWARDLY FROM THE BODY AT ONE SIDE OF THE OPENING TO SCRAPE PARAFFIN FROM A WELL CASING, SAID BLADE ADAPTED TO BE POSITIONED ON THE LEADING EDGE OF THE OPENING WHEN THE ROD IS ROTATED THEREBY TIGHTENING THE SCRAPER ON THE ROD, AND A STOP LUG ON THE 